| With the development of science and the improvement of agricultural mechanization,the performance of planter is getting higher and higher.As a result,the demand for the sowing opener is getting higher and higher.Aiming at the problems such as large soil disturbance,poor uniformity of seeding depth,shortage of soil compaction and severe mixing of dry and wet soil,a new integrated seeding furrow opener with trenching,covering and pressing functions is designed for seeding machine.The trench opener can realize sliding soil trench breaking and reducing soil disturbance,seed falling to the bottom of the ditch to improve the uniformity of seeding depth,and the wet soil preferential return ditch can be achieved by the cooperation of sliding knife,retaining plate,suppressing wheel,etc.Reduce dry and wet soil mixing;suppress seed trenches and increase seed contact with soil.On the basis of comprehensive study to the research results of seeding trench openers at home and abroad,aiming at the problems existing in seeding operation in northeast ridge area,a combined seeding furrow opener was studied by combining theoretical analysis with experimental research.The main research of this paper is as follows:(1)In view of the problems existing in seeding operation,based on the idea of integration,the integral structure of the combined seeding furrow opener(such as sliding knife,retaining plate,repressing wheel and so on)is determined,which can meet the requirements of covering soil and repressing the soil while opening the seeding ditch.Improve the quality of seeding operation.The key parts of the combined seeding furrow opener are analyzed in theory.By analyzing the principle of sliding cutting,the mechanism of soil reflux and the mechanism of suppression,the slip angle of the knife,the inclination of the retaining plate and the deformation of the spring are determined as the important parameters of the furrow opener.Through theoretical analysis and agronomic requirements,the parameters were obtained as follows: slip angle 25°~ 65°,slope angle 0°~ 12°,spring variable 4 ~ 20 mm.(2)In order to obtain the seeding performance of the new type of seeder,a combined seeding furrow opener was tested.Firstly,the soil disturbance,soil compactness and sowing depth were taken as the test index,the slip angle of the slide knife and the dip angle of the retaining plate were taken as the test index.Spring deformation was used as the experimental factor to test the new type furrow opener in the field.The results showed that three factors had a great effect on the soil disturbance and soil compactness,and the influence of each factor on the test index was investigated.It has little influence on sowing depth.The comparison test of seeding performance was carried out between the double disc trench opener and combined seeding furrow opener in Northeast China.The coefficient of variation of seeding depth of new type trench opener and double disc trench opener is 3.61% and 7.34% respectively.The combined seeding furrow opener can improve the uniformity of seeding depth and has good seeding performance.The whole structure of the combined seeding furrow opener can reduce the mixing of dry and wet soil.(3)The parameter optimization test of a combined seeding furrow opener is carried out in order to find the optimal parameter combination of the furrow opener and to provide a reference idea for the design of the seeding furrow opener.First of all,soil moisture content,slip angle of slide knife,slope angle of retaining plate,spring deformation as test factors,traction resistance,soil disturbance and soil compactness are the test indexes.The experiment design software Design-Expert 8.0.6 was used to carry out four factors and five levels quadratic regression orthogonal rotation combination test.The optimum parameters of the new integrated seeding ditch opener were obtained as follows: soil moisture content 16.98,slide angle 41.87°,retaining plate angle 3.50°,spring variable 12 mm.Then the combined seeding furrow opener and the double disc trench opener under the best parameters are selected to carry on the contrast test in field.It indicated that the combined seeding furrow opener could effectively improve the soil environment of seed bed,enhance soil compactness and further improve the quality of seeding operation.It can be used for reference in the design of combined seeding furrow opener.The combined seeding furrow opener can effectively improve the soil environment of seeding bed,enhance soil compactness,further improve the quality of seeding operation,and provide a reference idea for the design of combined seeding furrow opener. |
